U.S. patent number 5,364,376 [Application Number 07/926,530] was granted by the patent office on 1994-11-15 for convertible catheter.
This patent grant is currently assigned to Danforth Biomedical Incorporated. Invention is credited to Michael J. Horzewski, Jeffrey L. Kraus.
United States Patent |
5,364,376 |
Horzewski , et al. |
November 15, 1994 |
Convertible catheter
Abstract
The present invention is a catheter having a guidewire lumen
slidable sleeve. The lumen and sleeve have aligned apertures, which
may be closed by moving the slidable sleeve. When the apertures are
aligned, a guidewire may be loaded from the distal end of the
catheter through the lumen. The guidewire is forced out of the
lumen by a ramp in the lumen. The ramp is at the end of a removable
core member, which provides enhanced shaft rigidity. The catheter
may be converted from a "monorail" to an "over-the-wire"
configuration by moving the slidable sleeve to close the aperture
and advancing a replacement guidewire through the guidewire lumen
past the now sealed aperture. A non-circular cross-section is used
for the lumen, removable core member, and slidable sleeve, thereby
maintaining orientation of the lumen and slidable sleeve apertures
should the catheter undergo rotational flexing during use.
Inventors: |
Horzewski; Michael J. (San
Jose, CA), Kraus; Jeffrey L. (San Jose, CA) |
Assignee: |
Danforth Biomedical
Incorporated (Menlo Park, CA)
|
Family
ID: |
25453336 |
Appl.
No.: |
07/926,530 |
Filed: |
August 4, 1992 |
Current U.S.
Class: |
604/528;
604/247 |
Current CPC
Class: |
A61M
25/0169 (20130101); A61M 25/0172 (20130101); A61M
29/02 (20130101); A61M 25/0029 (20130101); A61M
25/0032 (20130101); A61M 25/0075 (20130101); A61M
2025/0183 (20130101) |
Current International
Class: |
A61M
29/02 (20060101); A61M 25/01 (20060101); A61M
25/00 (20060101); A61M 025/00 () |
Field of
Search: |
;604/164,96-103,280,52,53,181,269,249,256,266,267,264,247
;606/194,27-29,192,198 ;128/656,657,658,772 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
|
|
|
|
|
0282143 |
|
Jan 1988 |
|
EP |
|
0380873 |
|
Dec 1989 |
|
EP |
|
9211894 |
|
Jul 1992 |
|
WO |
|
Primary Examiner: Rosenbaum; C. Fred
Assistant Examiner: Alexander; V.
Attorney, Agent or Firm: Jaffer; David H.
Claims
What is claimed is:
1. A catheter adapted for reversible conversion from a rapid
exchange configuration to an over-the-wire configuration,
comprising:
(a) a catheter having a guidewire lumen with proximal and distal
apertures and an intermediate aperture situated between the
proximal and distal apertures, whereby a guidewire may be loaded
through the distal and intermediate apertures; and
(b) movable means for closing the intermediate aperture, thereby
permitting a guidewire to be loaded through the proximal aperture
to the distal end of the guidewire lumen while preventing exit of
the guidewire through the intermediate aperture.
2. The catheter of claim 1, wherein the means for closing the
intermediate aperture comprises a sleeve which may be moved
relative to the guidewire lumen, thereby closing and opening the
intermediate aperture.
3. The catheter of claim 2, wherein the sleeve and the guidewire
lumen have non-circular cross-sections.
4. The catheter of claim 2, wherein the proximal end of the sleeve
is attached to a fitting, the fitting having a guide for indicating
the relative positions of the sleeve and the guidewire lumen,
thereby indicating when the intermediate aperture is open and
closed.
5. The catheter of claim 2, wherein the sleeve lies inside the
walls of the guidewire lumen.
6. The catheter of claim 2, wherein a portion of the sleeve is
thickened, thereby providing greater ability to manipulate the
sleeve.
7. The catheter of claim 2, wherein the sleeve is formed of a
lubricious material.
8. The catheter of claim 2, wherein the sleeve lies outside the
walls of the guidewire lumen.
9. The catheter of claim 1, wherein the means for closing the
intermediate aperture comprises a flexible flap adjacent to the
intermediate aperture.
10. The catheter of claim 1, further comprising a removable core
member in the portion of the guidewire lumen proximal to the
intermediate aperture.
11. The catheter of claim 10, wherein the means for closing the
intermediate aperture comprises a flexible flap adjacent to the
intermediate aperture.
12. The catheter of claim 10, wherein the distal end of the core
member includes means for directing a guidewire out of the
guidewire lumen through the intermediate aperture.
13. The catheter of claim 10, wherein the means for closing the
intermediate aperture comprises a sleeve which may be moved
relative to the guidewire lumen, thereby closing and opening the
intermediate aperture.
14. A method for converting a catheter from a rapid exchange
configuration to an over-the-wire configuration, comprising:
(a) loading a first guidewire through distal and intermediate
apertures in a guidewire lumen of the catheter, the intermediate
aperture situated between the distal aperture and a proximal
aperture in the guidewire lumen;
(b) removing the first guidewire;
(c) movably closing the intermediate aperture in the guidewire
lumen to prevent exit through the intermediate aperture; and
(d) loading a second guidewire through the proximal aperture to the
distal end of the guidewire lumen.
15. The method of claim 14, wherein the step of closing the
intermediate aperture comprises moving a sleeve relative to the
guidewire lumen, thereby closing the intermediate aperture.
16. The method of claim 15, wherein the proximal end of the sleeve
is attached to a fitting, the fitting having a guide for indicating
the relative positions of the sleeve and the guidewire lumen,
thereby indicating when said intermediate aperture is open and
closed.
17. The method of claim 14, wherein the portion of the guidewire
lumen proximal to the intermediate aperture has a removable core
member to enhance pushability of the catheter thereby aiding in
positioning of the catheter, and after such positioning the core
member being removed from the guidewire lumen prior to loading of
the second guidewire.
18. The method of claim 14, wherein the steps of closing the
intermediate aperture and loading the second guidewire move a
flexible flap adjacent to the intermediate aperture, thereby
closing the intermediate aperture.
19. The method of claim 18, wherein the portion of the guidewire
lumen proximal to the intermediate aperture has a removable core
member to enhance pushability of the catheter, thereby aiding in
positioning of the catheter, and after such positioning the core
member being removed from the guidewire lumen prior to loading of
the second guidewire.
20. The method of claim 14, further comprising the steps of:
(a) removing the second guidewire from the guidewire lumen;
(b) movably opening the intermediate aperture in the guidewire
lumen; and
(c) loading a third guidewire through the intermediate and distal
apertures.
21. A method for converting a catheter from an over-the-wire
configuration to a rapid exchange configuration, comprising:
(a) removing a first guidewire from a guidewire lumen of the
catheter, the first guidewire prior to removal extending between a
proximal aperture in the guidewire lumen and the distal end of the
guidewire lumen;
(b) movably opening an intermediate aperture in the guidewire
lumen, the intermediate aperture situated between a distal aperture
and the proximal aperture in the guidewire lumen; and
(c) loading a second guidewire through the intermediate and distal
apertures.
22. The method of claim 21, wherein the step of opening the
intermediate aperture comprises moving a sleeve relative to the
guidewire lumen, thereby opening the intermediate apertures.
23. The method of claim 22, wherein the proximal end of the sleeve
is attached to a fitting, the fitting having a guide for indicating
the relative positions of the sleeve and the guidewire lumen,
thereby indicating when said intermediate aperture is open and
closed.
24. The method of claim 21, further comprising the step of
inserting a core member into the portion of the guidewire lumen
proximal to the intermediate aperture, the core member providing
enhanced pushability of the catheter after removal of the first
guidewire.
25. The method of claim 21, wherein the step of opening the
intermediate aperture comprises moving a flexible flap adjacent to
the intermediate aperture, thereby opening the intermediate
aperture.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to an exchangeable catheter, and
more particularly to a catheter which is convertible from one which
permits simple and rapid exchange of catheters while a guidewire is
in place to a catheter which allows guidewires to be exchanged
while the catheter is in place.
2. Brief Description of the Prior Art
Various configurations of catheters and guidewires have been
developed over the years for the purpose of satisfying different
functional requirements. "Over-the-wire" catheter systems permit
full rotational and full coaxial mobility of the guidewire relative
to the catheter component of the system. "Over-the-wire" catheters
can be fully withdrawn over a guidewire, and they will accept the
antegrade and retrograde introduction of a guidewire therethrough.
U.S. Pat. No. 4,323,071 describes an "over-the-wire" system.
While "over-the-wire" systems allow for exchange of catheters along
the fixed guidewire and vice versa, such replacement is
mechanically difficult because "over-the-wire" systems require that
the guidewire protrude from the patient's body by a length greater
than the length of the catheter. Thus, manipulation of the catheter
during catheter replacement is difficult.
A different type of catheter-guidewire system has been developed to
address this problem. Known generically as "rapid exchange" or
"monorail" catheters, the design permits catheter exchange over a
standard 175 cm length guidewire. U.S. Pat. Nos. 4,762,129 to
Bonzel, 4,748,982 to Horzewski et al., and 5,040,548 to Yock teach
variations of such designs. The designs include an inflation lumen
within the catheter which runs the length of the catheter, and a
separate guidewire lumen which extends a relatively short distance
from the distal end toward the proximal end of the catheter. Since
the guidewire lumen is relatively short compared to the overall
length of the catheter, when one catheter is withdrawn over the
guidewire and replaced with another guidewire, only the relatively
short guidewire lumen needs to be threaded over the fixed
guidewire.
The "monorail" concept has been readily accepted because it permits
simple and rapid catheter exchange. However, a major problem of the
design is that once a "monorail" catheter has been positioned, the
guidewire is extremely difficult to exchange. This is because the
guidewire lumen is relatively short. When the catheter is in place
and the guidewire is withdrawn, it is impractical to locate the
guidewire lumen with a replacement guidewire while the "monorail"
catheter (and entrance to the guidewire lumen) is within a
patient's body.
SUMMARY OF THE INVENTION
It is a primary objective of the present invention to provide a
convertible catheter design which allows the catheter to change
configuration from one which can be exchanged over a standard 175
cm length guidewire to an "over-the-wire" catheter which allows
guidewires to be exchanged while the catheter is in place. The
design similarly permits reintroduction of substitute catheters
after guidewire exchange.
Another object of the present invention is to provide a slidable
sleeve on the catheter which permits conversion from the "monorail"
to "over-the-wire" concepts, through advancement, retraction, or
rotation of the slidable sleeve.
A further object of the present invention is to provide catheter
core member which enhances shaft rigidity and facilitates guidewire
exiting when the catheter is threaded over the guidewire.
Briefly, the preferred embodiment of the present invention
comprises a catheter having a guidewire lumen with a slidable
sleeve. The lumen and sleeve have aligned apertures, which may be
closed by retracting, advancing, or rotating the slidable sleeve.
When the apertures are aligned, a guidewire may be loaded from the
distal end of the catheter through the lumen. The guidewire is
forced out of the lumen by a ramp or flap in the lumen. Preferably,
the ramp is on the end of a removable core member, which provides
enhanced shaft rigidity. This "monorail" configuration may be
converted to an "over-the-wire" configuration by removing the first
guidewire, withdrawing the core member, moving the slidable sleeve
to close the aperture, and advancing a replacement guidewire
through the lumen past the now sealed aperture. The lumen with
aperture, removable core member, and slidable sleeve with aperture
are preferably non circular in cross-section, to maintain
orientation of the lumen and slidable sleeve apertures should the
catheter undergo any rotational flexing during use.
The objects above and other objects and advantages of the present
invention will no doubt become apparent to those skilled in the art
after having read the following detailed description of the
preferred embodiment which is contained in and illustrated by the
various drawing FIGS.
IN THE DRAWINGS
FIG. 1 is a cross-sectional view of three segments of the preferred
embodiment of this invention taken along the lengthwise axis of the
device;
FIG. 2 is a cross-sectional view of a portion of the preferred
embodiment of this invention taken along the lengthwise axis of the
device, with the apertures in the guidewire lumen and slidable
sleeve aligned to permit guidewire loading;
FIGS. 3(a), 3(b), 3(c), and 3(d) are cross-sectional views of the
device shown in FIG. 2, taken along lines A--A, B--B, C--C, and
D--D of FIG. 2 and perpendicular to the lengthwise axis of the
device;
FIG. 4 is a cross-sectional view of the device shown in FIG. 1,
with the core member removed;
FIG. 5 is a cross-sectional view of the device shown in FIG. 4,
taken along line A--A of FIG. 4;
FIG. 6 is a cross-sectional view of the device shown in FIG. 2,
with the slidable sleeve retracted so that the apertures in the
guidewire lumen and slidable sleeve are offset, causing the lumen
to be closed;
FIGS. 7(a), 7(b), and 7(c) are cross-sectional views of the device
shown in FIG. 6, taken along lines A--A, B--B, and C--C of FIG.
6;
FIGS. 8(a) and 8(b) show an alternative embodiment of the present
invention, in which the slidable sleeve is on the exterior of the
catheter; and
FIGS. 9(a) and 9(b) show a second alternative embodiment of the
present invention, in which a flap is substituted for the slidable
sleeve.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
This invention provides a catheter device that is conveniently and
dependably convertible from a "monorail" design, with its
advantages of simple and rapid exchange, to an "over-the-wire"
design which permits guidewire exchange. The design also permits
reintroduction of "monorail" catheters after guidewire exchange,
should this be desired. For simplicity, the invention is described
below with specific reference to its preferred embodiment in a
multilumen angioplasty catheter. However, the design is suitable to
both coaxial and multilumen catheter designs, and may be applied to
any type of catheter.
Referring now to FIG. 1 of the drawing, a distal portion 40 of a
multilumen dilatation catheter is shown. The walls 12 of the
catheter define an inflation lumen 14 and a guidewire lumen 16.
Near the distal end of the catheter, an inflatable balloon 42 is
attached to the walls 12 of the catheter. The location of the
catheter within a patient's body may be detected through a
radiographic technique which identifies metal band 44 which is
located on the walls 12 of the catheter in an approximately central
location of inflatable balloon 42.
With reference to FIGS. 1 and 2, a portion 10 of a multilumen
catheter is shown. The catheter portion 10 is situated a convenient
distance from the distal end of the catheter. In general, in an
angioplasty catheter as known in the prior art, this catheter
portion 10 would be located from 3 to 30 cm from the distal end of
the catheter. However, the exact distance is not critical, provided
that portion 10 shown is located a convenient distance from the
distal end to permit trackability over the guidewire.
In FIG. 2, the distal end of the catheter extends beyond the right
hand side of the drawing. The walls 12 of the catheter define
inflation lumen 14 and guidewire lumen 16. Typical construction of
catheters uses a variety of materials to provide the desired
properties of flexibility and pushability. For example, high
density materials are used for enhanced pushability and strength,
while lower density materials provide more flexibility. Catheters
may be composed of a combination of these materials in different
proportions throughout the length of the catheter.
A slidable sleeve 18 is shown within guidewire lumen 16 in FIG. 2.
Slidable sleeve 18 is formed of a lubricious material, such as high
density polyethylene or fluorinated polymers, which allows the
slidable sleeve to move relatively easily within the walls 12 of
guidewire lumen 16. Slidable sleeve 18 may extend any length toward
the distal end of the catheter. Walls 12 of the guidewire lumen 16
preferably are internally lubricious, to facilitate movement of
slidable sleeve 18, while also being externally bondable, for
example to permit affixation of inflatable balloon 42 shown in FIG.
1.
Referring again to FIG. 2, removable core member 24 is inserted in
guidewire lumen 16 to provide enhanced "push" for the catheter.
Typically, core member 24 would be comprised of a materials such as
titanium, titanium alloys (e.g. nickel titanium), or stainless
steel. Core member 24 tapers through a tapered portion 36 to a
thinner portion 32. The tapering of core member 24 enhances its fit
within slidable sleeve 18, which has a corresponding thinner
portion 30 and thicker portion 28 to conform to the tapering of
core member 24. The tapering of core member 24 and slidable sleeve
18 may be gradual or in a stairstep pattern, but only one tapering
is shown in FIG. 2 for the sake of simplicity. Tapering of core
member 24 and slidable sleeve 18 is done in a manner that transmits
push from core member 24 to the catheter shaft.
Both catheter wall 12 and slidable sleeve 18 are cut to define
catheter wall aperture 20 and slidable sleeve aperture 22, creating
an exit opening from guidewire lumen 16. Removable core member 24,
when positioned in guidewire lumen 16, terminates near apertures 20
and 22. When catheter wall aperture 20 and slidable sleeve aperture
22 are aligned as in FIG. 2, guidewire lumen 16 may be loaded with
a guidewire from the distal end of catheter 10 (toward the right of
FIG. 1) through guidewire lumen 16. When the guidewire contacts
ramp 26 on the distal end of core member 24, the guidewire is
directed out of the catheter through aligned apertures 22 and 20 in
slidable sleeve 18 and catheter wall 12.
An advantage of the thickened portion 28 of slidable sleeve 18 is
that this thickened portion 28 may be stiffened to provide greater
ability to manipulate the aperture in the slidable sleeve for the
purposes discussed below. It also improves the transition between
the proximal and distal portions of the catheter shaft and
throughout the aperture region. This is useful because the
transition from the end of core member 24 to the more flexible
portion of the catheter shaft immediately distal thereof can be
severe. It is helpful to "reinforce" this region and smooth out the
transition.
With reference to FIGS. 3(a), 3(b), 3(c), and 3(d), cross-sectional
views of the device shown in FIG. 2 are shown, taken along lines
A--A, B--B, C--C, and D--D of FIG. 2 and perpendicular to the
lengthwise axis of the catheter.
FIG. 3(a) shows wall 12 of the catheter, in which are defined
inflation lumen 14 and guidewire lumen 16. In FIG. 3(a), guidewire
lumen 16 is filled with thinner portion 30 of slidable sleeve 18
and thicker portion 34 of removable core member 24. FIG. 3(b) shows
a cross-section of the catheter somewhat closer to the distal end.
Guidewire lumen 16 is filled now with thickened portion 28 of
slidable sleeve 18, and thinner portion 32 of removable core member
24. FIG. 3(c) is taken at a portion of the catheter where catheter
wall aperture 20 and slidable sleeve aperture 22 are aligned. Thus,
guidewire lumen 16 is open to the exterior of the catheter. FIG.
3(d) shows a portion of the catheter closer to the distal end. In
this case, thickened portion 28 of slidable sleeve 18 is located
within guidewire lumen 16 defined by catheter wall 12.
FIG. 4 depicts catheter portion 10 after core member 24 has been
removed. Guidewire lumen 16 is now open from the distal to the
proximal end of the catheter. However, guidewire lumen 16 remains
open to the exterior of the catheter because catheter wall aperture
20 and slidable sleeve aperture 22 are still aligned.
FIG. 5 shows a cross-sectional view of the catheter taken on the
proximal side of apertures 20 and 22. Wall 12 of the catheter
defines guidewire lumen 16 with thickened portion 28 of slidable
sleeve 18 situated on the outer periphery of guidewire lumen
16.
With reference to FIG. 6, slidable sleeve 18 has been moved
relative to the remainder of catheter portion 10. Slidable sleeve
aperture 22 is no longer aligned with catheter wall aperture 20.
This closes the opening in guidewire lumen 16 and permits a
guidewire to be loaded from the proximal end of the catheter (at
the left of FIG. 6) toward the distal end of the catheter. The
order of removing core member 24 and moving slidable sleeve 18 may
be reversed.
Now a replacement guidewire may be put into place without removing
the catheter, and with certainty that guidewire lumen 16 provides a
continuous path through the overall catheter length from proximal
to distal end. FIGS. 7(a) and 7(b) illustrate this, showing that
guidewire lumen 16 no longer has an opening because catheter wall
12 now covers slidable sleeve aperture 22, and thickened portion 28
of slidable sleeve 18 now covers catheter wall aperture 20. Thus, a
guidewire may be threaded through the entire length of guidewire
lumen 16, without risk that the guidewire will exit through what
was formerly an opening in guidewire lumen 16 when slidable sleeve
aperture 22 and catheter wall aperture 20 were aligned.
After a guidewire has been inserted in guidewire lumen 16 from the
proximal to distal end of the catheter, the catheter serves as a
"over-the-wire" catheter. Wires may be replaced easily through
guidewire lumen 16. In the event that it should become necessary to
substitute catheters, the catheter may be removed along the
guidewire while maintaining the guidewire in place, in the standard
"over-the-wire" manner. Once the catheter has been removed with the
guidewire remaining in place, a new catheter may be substituted.
This new catheter may be of the "monorail" or "over-the-wire"
varieties, or may be a convertible catheter as taught by this
invention.
It should be noted that the opening in guidewire lumen 16 may be
closed either through retracting slidable sleeve 18 as shown in
FIG. 6, or by advancing the slidable sleeve. In the preferred
embodiment, guidewire lumen 16, slidable sleeve and removable core
member 24 all have noncircular cross-sections which serve to
maintain alignment of apertures 20 and 22, should the catheter
undergo any rotational flexing during use. However, in an
alternative embodiment the apertures in the guidewire lumen and
slidable sleeve could be closed by rotating the sleeve with respect
to the guidewire lumen, particularly their cross-sections are
relatively circular.
Referring back to FIG. 1, a third portion 50 of the multilumen
catheter is shown. Catheter portion 50 is the proximal end of the
catheter. Portion 50 includes walls 12 of the catheter defining
inflation lumen 14 and a guidewire lumen. The guidewire lumen
(shown as 16 in portion 10 of the catheter) is filled with
removable core member 24. Slidable sleeve 18 is shown extending to
the proximal end of the catheter. The proximal portion 50 of the
catheter terminates in a first fitting 52 adapted to serve several
functions. First fitting 52 is attached to walls 12 of the
catheter, and includes an inflation port 53 through which an
inflation fluid may be added to inflation lumen 14 for inflating
balloon 42.
Knob 25 is attached to removable core member 24 so that removable
core member 24 may be easily removed from the catheter, leaving
guidewire lumen 16 open and available for entry by a guidewire.
Second proximal fitting 19 is attached to slidable sleeve 18,
permitting slidable sleeve 18 to be manipulated from the proximal
end of the catheter. Second fitting 19 includes an annular ring 21
which fits into notch 54 in first fitting 52 when, as discussed
above, slidable sleeve 18 is in a position such that catheter wall
aperture 20 and slidable sleeve aperture 22 are aligned. Second
fitting 19 may be compressed after core member 24 is removed,
permitting annular ring 21 to be moved from notch 54 to notch 56,
thereby moving slidable sleeve 18 with respect to catheter wall 12,
misaligning catheter wall aperture 20 and slidable sleeve aperture
22, and closing guidewire lumen 16.
With reference to FIGS. 8(a) and 8(b), an alternative embodiment is
shown. In this embodiment, catheter portion 60 is similar to
catheter portion 10 shown in FIG. 2, except that the slidable
sleeve is mounted on the exterior of the catheter walls. In FIG.
8(a), walls 62 of the catheter define inflation lumen 64 and
guidewire lumen 66. Guidewire lumen 66 is filled with removable
core member 74. Slidable sleeve 68 is exterior to catheter walls
12. As shown in FIG. 8(a), core member 74, catheter wall aperture
70, and slidable sleeve 68 are initially aligned to permit
guidewire loading from the distal end of the catheter, as discussed
above.
FIG. 8(b) shows catheter portion 60 after core member 74 has been
removed, and catheter walls 62 and slidable sleeve 68 have been
moved relative to each other, closing guidewire lumen 66 with
respect to the exterior of the catheter. Thus, guidewire lumen 66
is now sealed, and a new guidewire may be advanced from the
proximal to the distal end of guidewire lumen 66.
FIGS. 9(a) and 9(b) show another alternative embodiment of the
invention. In FIG. 9(a), catheter portion 80 corresponds to
catheter portion 10 shown in FIG. 2. FIGS. 9(a) and 9(b) show
catheter walls 82, inflation lumen 84, guidewire lumen 86, and
removable core member 94. FIG. 9(a) shows a flap portion 83 of
catheter wall 82, which in FIG. 9(a) is situated to provide
catheter wall aperture 90. In this configuration, flap 83 permits
guidewire loading from the distal end of the catheter through
guidewire lumen 86. Core member 94 reinforces flap 83, so that when
a guidewire is loaded from the distal end of the catheter, the
guidewire exits through catheter wall aperture 90.
If it is desired to convert the catheter to an over-the-wire type
catheter, core member 94 is removed. FIG. 9(b) shows this
embodiment after conversion to an over-the-wire type catheter. A
guidewire 85 is loaded through the proximal end of the catheter,
causing catheter flap portion 83 to be lifted to close guidewire
lumen 86 to the exterior of the catheter. The material used for
flap portion 83 preferably is a pliable material which when pressed
against another portion of the catheter wall 82 adheres. In FIG.
9(a), flap portion 83 is attached to the catheter wall in a manner
that keeps catheter wall aperture 90 open. Similarly, FIG. 9(b)
shows that after flap portion 83 is forced upward by the force of
guidewire 85, flap portion 83 closes guidewire lumen 86 to the
exterior of the catheter, preferably adhering to the upper portion
of catheter wall 82.
Although the present invention has been described in terms of
specific embodiments, it is anticipated that alterations
modifications thereof will no doubt become apparent to those
skilled in the art. It is therefore intended that the following
claims be interpreted as covering all such alterations and
modifications as fall within the true spirit and scope of the
invention.
* * * * *